1. Field of the Invention
This invention relates to a method for the hydrolysis of the amide bond on the C-terminal side of L-asparagine, by the use of a hydrolase which is specific for only the amide bond on the C-terminal side of L-asparagine contained in a compound having a peptide chain which has at least one amide bond on the C-terminal side of L-asparagine, to a reagent for use in such hydrolysis, and also to a novel asparaginyl endopeptidase which is of the same description as the above hydrolase.
2. Description of Related Art
Methods for the hydrolysis of peptide bonds only on the N-terminal side or the C-terminal side of a specific amino acid residue which is contained in a peptide chain, in which the recognition is selective and specific, are essential procedures for the analysis of protein structure and for the modification of proteins.
At the present, methods by which this purpose can be achieved have been established for the hydrolysis of the peptide bond on the C-terminal side of L-lysine, for the hydrolysis of the peptide bond on the N-terminal side of L-lysine, for the hydrolysis of the peptide bond on the C-terminal side of L-arginine, for the hydrolysis of the peptide bond on the C-terminal side of L-glutaminate and L-aspartic acid, for the hydrolysis of the peptide bond on the N-terminal side of L-aspartic acid, and for the hydrolysis of the peptide bond on the C-terminal side of L-proline, all of which are methods involving biochemistry. There are also methods which involve organic chemistry for the cleavage of the peptide bond on the C-terminal side of L-methionine, the cleavage of the peptide bond on the N-terminal side of L-cysteine, and the cleavage of the peptide bond on the C-terminal side of L-tryptophan.
In protein engineering, methods for the specific cleavage of a particular peptide bond of each of various amino acids are desired. However, there has been no method for the specific cleavage of amino acids other than those mentioned above.